Laurel Electronics LT21R4 Ohms Resistance Transmitter, 0-20.000 kOhm Range, 4-20 mA Analog and RS232/RS485 Outputs, Dual 120 mA Relays, 10-48 Vdc Power User selectable precalibrated resistance ranges from 20.000 ohm to 200.00 kohm set to 0-20.000 kOhm Range. 2, 3 or 4-wire connection with lead resistance compensation. 4-20 mA, 4-20 mA, 0-10V or 10V analog output, user selectable and scalable. Includes RS232 or RS485 data I/O and two 120 mA AC/DC solid state relays. Powered by 10-48 Vdc or 12-34 Vac. Power, inputs and outputs are mutually isolated.